Michael Schumacher has warned against high expectations for his Mercedes team at next week's Spanish Grand Prix, despite some encouraging progress made at the Mugello test this week.

With Mercedes having shown well at the Circuit de Catalunya in pre-season testing, and its W03 already proven to be a winner, the team is viewed by many as a strong contender for victory at the next race.

However, Schumacher is playing down prospects - but says that the team's situation should improve over the forthcoming races thanks to some encouraging feedback from upgrades tested in Mugello.

"The positive thing about the test was that we could really concentrate on the developments we were aiming to work on," said Schumacher. "This should give us a good basis for further developments, even if maybe not for the next race to come.

"Barcelona is a track we have driven extensively on, and this is why we know that its characteristics do not exactly play fully into our hands. But then, we will definitely go there and try our best and at the same time keep on working for the things to come."

Team-mate Nico Rosberg believes that the team could head to Barcelona with slightly more confidence about its competitive situation after the lessons learned from Mugello.

"The test in Mugello this week was very positive for us, and I believe we will arrive in Barcelona with a much better understanding of the tyres and how we need to set our car up," said the German.

"Despite the familiarity of the track, there will still be a lot of work for us to do, and it should be a good challenge."